Protective end cap for tube end

ABSTRACT

A protective endpiece for the end of a tube ( 100 ), the endpiece comprises a sheath ( 2 ) about an axis ( 3 ) possessing a central housing ( 4 ) for receiving the end of the tube ( 100 ) and has an open end ( 5 ) and a closed end ( 6 ). The sheath is provided at its open end ( 5 ) with a ring ( 10 ) that is detachable from the sheath so that after the sheath ( 2 ) has been removed and the end of the tube ( 100 ) has been coupled to a piece of equipment ( 200 ), the ring forms a stopper on,the end of the tube ( 100 ) for closing the gap that exists between the end of the tube ( 100 ) and the equipment ( 200 ).

The present invention relates to a protective endpiece for the end of atube.

BACKGROUND OF THE INVENTION

Protective endpieces for the ends of tubes are known that are in theform of a sheath about an axis, presenting a central housing forreceiving the end of a tube, one end of the housing being open and theother end closed.

Such endpieces are commonly mounted on the ends of tubes in order toprotect them during storage, transport, and handling, and prior toconnection with a piece of equipment such as the body of a pneumatic orhydraulic component.

OBJECT AND SUMMARY OF THE INVENTION

The invention provides a protective endpiece for the end of a tube, theendpiece comprising a sheath about an axis possessing a central housingfor receiving the end of the tube and having an open end and a closedend, in which endpiece the sheath is provided at its open end with aring that is detachable from the sheath so that after the sheath hasbeen removed and the end of the tube has been coupled to a piece ofequipment, the ring forms a stopper on the end of the tube for closingthe gap that exists between the end of the tube and the equipment.

Thus, prior to the tube end being coupled to the equipment, the endpieceperforms its conventional function of protecting the end of the tube.When it is time to couple the end of the tube to the equipment inquestion, the ring is detached from the sheath and remains on the end ofthe tube, while the sheath is withdrawn to uncover the end of the tubeand to enable it to be coupled to the equipment. Once this coupling hasbeen achieved, the ring which remains in place on the end of the tube ispressed against the equipment so as to prevent impurities frompenetrating therein via the gap which exists between the equipment andthe end of the tube. In this state, the ring performs a closure memberor “dust-excluder” function for the coupling between the end of the tubeand the equipment.

In an advantageous embodiment, the detachable ring is made integrallywith the sheath, a breakable zone having weak mechanical characteristicsbeing provided at the junction between the ring and the sheath to enablesaid ring to be separated manually.

According to an advantageous characteristic of the invention, thedetachable ring presents an inside shoulder arranged to co-operate witha corresponding shoulder on the end of the tube to retain the detachablering on the end of the tube when an axial force is exerted on the sheathto withdraw it. The ring is thus itself held on the end of the tube andit becomes automatically detached from the sheath when sufficient axialforce is exerted thereon to remove it.

It is then advantageous for the detachable ring to present an insidediameter which is slightly smaller than the inside diameter of thesheath, the retaining shoulder of the detachable ring being provided atthe junction between said ring and the sheath.

According to another advantageous characteristic of the invention, thedetachable ring comprises a body adjacent to the sheath and designed tobe received between the end of the tube and the equipment, and ashoulder for pressing against the equipment. This provides closure thatis particularly efficient and convenient. It suffices merely todimension the body of the ring in such a manner that it is inserted witha certain amount of tightness between the equipment and the end of thetube. The resulting clamping then holds the ring in its stopper positionagainst the equipment without any need for other locking members, andalso reinforces the effectiveness of closure.

In which case, it is advantageous for the body of the detachable ring topresent an outside surface that is frustoconical. The conical shape ofthe ring body makes it easier to insert the body into the equipmentwhile simultaneously obtaining good clamping.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics and advantages of the invention will appear onreading the following description of a particular embodiment given byway of non-limiting example.

Reference is made to the accompanying drawings, in which:

FIG. 1 is a side view of a protective endpiece of the invention;

FIG. 2 is an axial section view of the FIG. 1 endpiece, ready forfitting onto a tube end;

FIG. 3 is a view analogous to FIG. 2, after the endpiece has been fittedon the tube end so as to protect it;

FIG. 4 is a view analogous to FIG. 3, an axial force being exerted onthe sheath and the inside shoulder of the detachable ring coming intoabutment against the corresponding shoulder at the end of the tube;

FIG. 5 is a view analogous to FIG. 4 with the ring being detached fromthe sheath after the connection between them has broken under the effectof the axial removal force;

FIG. 6 is a view analogous to FIG. 5, the sheath being removed from theend of the tube while the detached ring remains thereon alone; and

FIG. 7 is a side view of the end of the tube connected to a piece ofequipment, the detached ring of the endpiece then performing itsfunction as a closure member or “dust-excluder” between the end of thetube and the equipment.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the figures, and in particular with reference to FIGS.1 and 2, an endpiece 1 of the invention is used to protect the end of atube 100.

This endpiece comprises a sheath 2 about an axis 3 and possessing acylindrical central housing 4 with an open end 5 situated to the rightin the figures and a closed end 6 situated to the left. On the outside,the sheath 2 also has two annular projections 7, 8 to make it easier togrip in order to enable it to be pulled along the axis 3, as explainedbelow.

At its open end 5, the sheath 2 is provided with a ring 10 which isdetachable. Specifically, the ring 10 comprises a body 11 having aperipheral outside surface in the form of a truncated cone whose apex isdirected towards the sheath, and a shoulder 12 situated to the right ofthe body 11, i.e. at a distance from the sheath 2, and presenting abearing face 16 perpendicular to the axis 3 and facing the sheath 2. Thebody 11 of the ring 10 also possesses a left-hand edge 13 which isconnected to the front end 5 of the sheath 2.

In this case, the detachable ring 10 is formed integrally with thesheath 2. A breakable zone 14 is provided by means of a peripheralgroove where the left-hand edge 13 of the ring 10 meets the front end 5of the sheath 2. Because of its reduced thickness, this breakable zone14 is mechanically weakened sufficiently to enable the ring to beseparated from the sheath 2 manually by breaking said zone by exertingan axial traction force on the sheath 2, as explained below.

Finally, the ring 10 presents a cylindrical inside surface about theaxis 3 of diameter that is slightly greater than the diameter of thecentral housing 4 of the sheath 2 and substantially equal to the outsidediameter of the tube 100. At its right-hand end, this inside surface 17of the ring 10 presents a chamfer 18.

The reduction in diameter between the cylindrical housing 4 of thesheath 2 and the cylindrical inside surface 17 of the ring 10 gives riseto a shoulder 19 whose surface facing the sheath 2 is situated in thiscase in the same plane perpendicular to the axis 3 as the left-hand edge13 of the body 11 of the ring 10.

The endpiece is shipped in the configuration shown in FIGS. 1 and 2 andas described above, and it is used as follows.

The first function of the endpiece is to protect the end of the tube100. As mentioned above, the tube 100 has an outside diameter which issubstantially equal to the diameter of the inside surface 17 of the ring10. The tube 100 also possesses a shoulder 101 which is situated at acertain distance from its free end 105 and, with reference to thefigures, it presents a left-hand surface 103 forming a conical ramp, anda right-hand surface 102 situated in a plane that is substantiallyperpendicular to the axis of the tube 100.

As shown in FIG. 3, the endpiece 1 is fitted onto the end of the tube100 whose axis then coincides with the axis 3 of the endpiece. The endof the tube 100 is thus pushed into the housing 4 of the sheath 2 untilthe free end 105 of the tube comes into abutment against the closed end6 of the sheath. Before reaching this configuration in which theendpiece 1 is fully engaged on the end of the tube 100, as shown in FIG.3, the shoulder 101 must go past the ring 10 such that the face 102 ofthe shoulder 101 is situated to the left of the inside shoulder 19situated at the junction between the ring 10 and the sheath 2. In thisrespect, the conical shape of the left-hand face 103 of the shoulder 101of the tube 100 makes it easier to pass the shoulder 101 through thering 10 in spite of the diameter of the shoulder 101 being slightlygreater than the diameter of the inside surface 17 of said ring.

In this configuration, the endpiece 1 performs its conventionalprotection function on the end of the tube 100. It will be observed thatin the event of the endpiece 1 tending to slip off the end of the tube100 to the left, i.e. tending to become separated therefrom, as shown inFIG. 4, then the inside shoulder 19 provided at the junction between thering 10 and the sheath 2 comes into abutment against the left-hand face102 of the shoulder 101 at the end of the tube 100 so that the endpiece1 is retained on the tube 100. This prevents the end of the tube 100losing the protection provided by the endpiece 1 in untimely manner,e.g. while being handled or in transit.

When the end of the tube 100 is to be coupled to a piece of equipment200 (shown only in FIG. 7), then the end of the tube 100 is initiallyextracted from the sheath 2. For this purpose, and as shown in FIGS. 4and 5, traction force is exerted on the sheath 2 along the axis 3towards the left. This traction force seeking to remove the sheath 2axially is exerted manually, and the user's grip on the sheath 2 is madeeasier and more reliable by the presence of the two annular projections7, 8 on the outside surface of the sheath 2. However, the ring 10 isretained by the internal shoulder 19 coming into abutment against theright-hand face 102 of the shoulder 101 at the end of the tube 100. Oncethe magnitude of the withdrawal force becomes sufficient, the breakablezone 14 provided at the junction between the ring 10 and the sheath 2breaks, so the ring 10 becomes separated from the sheath.

The sheath 2 can then be withdrawn from the end of the tube 100 so as toleave it disengaged, as shown in FIG. 6. Nevertheless, it will beunderstood that in this configuration, the ring 10, now separated fromthe sheath 2, remains in place on the end of the tube 100, as can beseen in FIG. 6.

The end of the tube 100 can then be coupled to a piece of equipment suchas that represented diagrammatically at 200 in FIG. 7. Coupling is bymeans of a conventional coupling device which does not constitute thesubject matter of the present invention and which is therefore notdescribed further.

Once this coupling has been achieved, the ring 10 which is still inplace on the end of the tube 100 is pressed against the equipment 200 toform a closure member or “dust-excluder” preventing impurities frompenetrating into the gap that remains between the equipment 200 and theend of the tube 100. More precisely, the body 11 of the ring 10 ispushed like a cork into the gap that remains between the equipment 200and the end of the tube 100 and it is inserted tightly into this gap,with insertion and tightening inside the equipment 200 being made easierand more reliable by the peripheral surface 15 of the body 11 of thering 10 being conical. The closure and protection of the gap that existsbetween the equipment 200 and the end of the tube 100 are finished offby the shoulder of the ring 10 being pressed like a washer or a capagainst the equipment 200, the face 16 of said shoulder coming intoabutment against a corresponding face 201 of the equipment 200.

The invention is not limited to the embodiment described above, but onthe contrary covers any variant using equivalent means to reproduce theessential characteristics of the invention.

In particular, although the detachable ring in the above-describedexample is formed integrally with the sheath, it would be equallypossible to make an endpiece of the invention in which the detachablering is made initially as a piece that is separate from the sheath.Under such circumstances, temporary breakable connection means areprovided to secure the ring 10 temporarily to the sheath 1 until anaxial force tending to separate the ring from the sheath causes theconnection means to give way so as to enable the ring to be separatedfrom the sheath. By way of example, an assembly could be provided usinga tight-fit and/or snap-fastening engagement, adhesive, or any otherfixing means presenting a weak or breakable zone.

In addition, although the detachable ring is provided in the above-shownexample with an inside shoulder situated in the same plane as its ownleft-hand edge (relative to the drawings), it is equally possible toprovide a detachable ring which is provided with an inside shoulder thatis set further back, i.e. further towards the right (with reference tothe figures) than its left-hand edge, the essential point being thatsaid shoulder must be capable of co-operating with a corresponding faceof a shoulder at the end of the tube.

Although this inside shoulder is advantageous insofar as it enables thedetachable ring to be retained automatically on the end of the tube, itis nevertheless not essential. An endpiece of the invention could bemade having a detachable ring that does not have any inside shouldersuitable for holding it on the end of the tube. For example, the insidesurface of the ring (reference 17 in the figures) could extend in linewith the surface of the central housing of the sheath (reference 4 inthe figures). It would then suffice for detaching the ring from thesheath to exert opposing axial forces on the ring and on the sheath, orindeed twisting forces, seeking to separate them. For this purpose, itis possible to make use of the grip made available by the shoulder 12 ofthe ring.

What is claimed is:
 1. A protective endpiece for the end of a tube(100), the endpiece comprising: a sheath (2) about an axis (3)possessing a central housing (4) for receiving the end of the tube (100)and having an open end (5) and a closed end (6), wherein the sheath isprovided at its open end (5) with a ring (10) that is detachable fromthe sheath, wherein said ring comprises a body (11) adjacent to saidsheath and a shoulder (12) spaced from said sheath so that after thesheath (2) has been removed and the end of the tube (100) has beencoupled to a piece of equipment (200), the ring forms a stopper on theend of the tube (100) with said body (11) for closing the gap thatexists between the end of the tube (100) and the equipment (200).
 2. Aprotecting endpiece according to claim 1, wherein the detachable ring(10) is made integrally with the sheath (2), a breakable zone (14)having weak mechanical characteristics being provided at the junctionbetween the ring (10) and the sheath (2) to enable said ring to beseparated manually.
 3. A protective endpiece according to claim 1,wherein the detachable ring (10) presents an inside shoulder (19)arranged to co-operate with a corresponding shoulder (102) on the end ofthe tube (100) to retain the detachable ring (10) on the end of the tube(100) when an axial force is exerted on the sheath (2) to withdraw it.4. A protective endpiece according to claim 3, wherein the detachablering (10) presents an inside diameter which is slightly smaller than theinside diameter of the sheath (2), the retaining shoulder (19) of thedetachable ring (10) being provided at the junction between said ringand the sheath (2).
 5. A protective endpiece according to claim 1,wherein the body (11) of the detachable ring (10) presents an outsidesurface that is frustoconical.